Seismic investigations from the Qinling-Dabie-Sulu orogenic belt in eastern China suggest that this region was affected by extreme mantle perturbation and crust-mantle interaction during the Mesozoic era. ...

Earth's magnetic field is crucial for our existence, as it shields the life on our planet's surface from deadly cosmic rays. It is generated by turbulent motions of liquid iron in Earth's core. Iron is a ...

Miranda, a small, icy moon of Uranus, is one of the most visually striking and enigmatic bodies in the solar system. Despite its relatively small size, Miranda appears to have experienced an episode of intense ...

An infrared image from NOAA's GOES-West satellite showed what appeared to be a ghostly ring of clouds and no convection in former Hurricane Cristina on Monday, June 16 as the system weakened to a remnant ...

Understanding how clouds affect the climate has been a difficult proposition. What controls the makeup of the low clouds that cool the atmosphere or the high ones that trap heat underneath? How does human ...

Scientists from the Magma and Volcanoes Laboratory (CNRS) and the European Synchrotron, the ESRF, have recreated the extreme conditions 600 to 2900 km below the Earth's surface to investigate the melting ...

Scientists have shown that temperature differences deep within Earth's mantle control the elevation and volcanic activity along mid-ocean ridges, the colossal mountain ranges that line the ocean floor. The ...

Seeking to better understand the composition of the lowermost part of Earth's mantle, located nearly 2,900 kilometers (1,800 miles) below the surface, a team of Arizona State University researchers has developed ...

(Phys.org) —A team of researchers at the University of Texas with assistance from a computer modeler at the Max Planck Institute in Germany has put together a computer model that might just explain the ...

NOAA's GOES-East satellite captured a visible image of Tropical Depression Lorenzo that showed very little convection happening throughout the system because of two environmental factors: dry air and cooler ...

Since 1993, oceanographers from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), have carried out regularly expeditions to the Greenland Sea on board the research ice breaker Polarstern ...

NASA's Aqua satellite caught the birth of the eighteenth tropical depression of the northwestern Pacific Ocean tropical cyclone season. Tropical Depression 18W was born in the South China Sea and is expected ...

NASA's TRMM satellite watched Tropical Storm Humberto's rainfall pick up over two days as it re-formed, and as part of NASA's HS3 mission, two of NASA's Global Hawk unmanned aircraft have been investigating ...

Convection

Convection is the movement of molecules within fluids (i.e. liquids, gases) and rheids. It cannot take place in solids, since neither bulk current flows nor significant diffusion can take place in solids.

Convection is one of the major modes of heat transfer and mass transfer. Convective heat and mass transfer take place through both diffusion – the random Brownian motion of individual particles in the fluid – and by advection, in which matter or heat is transported by the larger-scale motion of currents in the fluid. In the context of heat and mass transfer, the term "convection" is used to refer to the sum of advective and diffusive transfer. Note that in common use the term convection may refer loosely to heat transfer by convection, as opposed to mass transfer by convection, or the convection process in general. Sometimes "convection" is even used to refer specifically to "free heat convection" (natural heat convection), as opposed to forced heat convection. However, in mechanics the correct use of the word is the general sense, and different types of convection should be properly qualified for clarity.

Convection can be qualified in terms of being natural, forced, gravitational, granular, or thermomagnetic. It may also be said to be due to combustion, capillary action, or Marangoni and Weissenberg effects. Due to its role in heat transfer, natural convection plays a role in the stucture of Earth's atmosphere, its oceans, and its mantle. Discrete convective cells in the atmosphere can be seen as clouds, with stronger convection resulting in thunderstorms. Natural convection also plays a role in stellar physics.